Ground Water, continued

Quality of Water

The chemical character of the ground waters in Grant, Haskell, and Stevens Counties is indicated by the analyses in Table 11, Table 12, and Table 13. The analyses were made by H.A. Stoltenberg in the Water and Sewage Laboratory of the Kansas State Board of Health. Seventy-six samples of water were collected from representative wells distributed as uniformly as possible within the area and among the water-bearing formations, and one sample was collected from a gravel pit. The analyses of the water supplies at Ulysses (52), Sublette (183), Satanta (218), and Hugoton (296) are analyses of composite samples from two wells. The constituents listed were determined by methods used by the U. S. Geological Survey.

Chemical Constituents in Relation to Use

The following discussion of the chemical constituents of ground water in relation to use has been adapted from publications of the United States Geological Survey.

Dissolved solids--When water is evaporated the residue that is left consists mainly of the mineral constituents listed in the tables of analyses and generally includes a small quantity of organic material and a little water of crystallization. Waters containing less than 500 parts per million of dissolved solids generally are satisfactory for domestic use, except for difficulties resulting from their hardness or excessive content of iron. Waters containing more than 1,000 parts per million are likely to include enough of certain constituents to cause a noticeable taste or to make the water unsuitable in some other respects.

The dissolved solids in samples of water collected in Grant, Haskell, and Stevens Counties ranged from 162 to 1,474 parts per million, and 57 of the samples contained between 160 and 400 parts per million of dissolved solids (Table 14). More than 84 percent of the samples of water contained less than 500 parts per million and, therefore, are suitable for most ordinary uses.

Table 14--Dissolved solids in samples of water from wells in Grant, Haskell, and Stevens Counties.

Dissolved solids(parts per million)

Number of samples

Grant County

Haskell County

Stevens County

Total

101-200

2

13

0

15

201-300

1

10

11

22

301-400

9

0

11

20

401-500

4

2

2

8

501-600

2

1

2

5

601-700

1

0

0

1

701-800

2

0

0

2

801-900

0

0

0

0

901-1,000

0

0

0

0

More than 1,000

4

0

0

4

Total

25

26

26

77

Hardness--The hardness of water, which is the property that generally receives the most attention, is most commonly recognized by its effects when soap is used with the water in washing. Calcium and magnesium cause almost all the hardness of ordinary water. These constituents also are the active agents in the formation of most of the scale in steam boilers and in other vessels in which water is heated or evaporated.

In addition to the total hardness, the tables of analyses show the carbonate hardness and the noncarbonate hardness. The carbonate hardness is that caused by calcium and magnesium bicarbonates, and can be almost entirely removed by boiling. In some reports this type of hardness is called temporary hardness. The noncarbonate hardness is caused by sulphates or chlorides of calcium and magnesium, but it cannot be removed by boiling and has been called permanent hardness. With reference to use with soaps, there is no difference between the carbonate and noncarbonate hardness. In general the noncarbonate hardness forms harder scale in steam boilers.

Water having a hardness of less than 50 parts per million generally is rated as soft, and its treatment for the removal of hardness under ordinary circumstances is not necessary. Hardness between 50 and 150 parts per million does not seriously interfere with the use of water for most purposes; however, it does slightly increase the consumption of soap, and its removal by a process of softening is profitable for laundries or other industries using large quantities of soap. Waters in the upper part of this range of hardness will cause scale on steam boilers. Hardness above 150 parts per million can be noticed by anyone, and if the hardness is 200 or 300 parts per million it is common practice in some parts of the country to soften water for household use or to install cisterns to collect soft rain water. Where municipal water supplies are softened, an attempt generally is made to reduce the hardness to 60 or 80 parts per million. The additional improvement from further softening of a whole public supply is not deemed worth the increase in cost.

Water samples collected in Grant, Haskell, and Stevens Counties ranged in hardness from 144 to 809 parts per million. The hardness of 65 of the 77 samples of water ranged between 100 and 300 parts per million and the hardness of two samples of water exceeded 600 parts (Table 15).

Table 15-- Hardness of samples of water from wells in Grant, Haskell, and Stevens Counties.

Hardness(parts per million)

Number of samples

Grant County

Haskell County

Stevens County

Total

101-200

4

21

3

28

201-300

13

4

20

37

301-400

2

1

3

6

401-500

2

0

0

2

501-600

2

0

0

2

601-700

0

0

0

0

701-800

1

0

0

1

801-900

1

0

0

1

Total

25

26

26

77

Iron--Next to hardness, iron is the constituent of natural waters that in general receives the most attention. The quantity of iron in ground waters may differ greatly from place to place, even though the waters are derived from the same formation. If a water contains much more than 0.1 part per million of iron, the excess may precipitate and settle as a reddish sediment. Iron, which may be present in sufficient quantity to give a disagreeable taste and to stain cooking utensils, may be removed from most waters by simple aeration and filtration, but a few waters require the addition of lime or some other substance.

The iron content of samples of water from Grant, Haskell, and Stevens Counties ranged from 0.02 to 18 parts per million. Most of the samples of water (55), however, contained between 0.1 and 2 parts per million of iron and only six samples contained more than 8 parts (Table 16).

Table 16--Iron content of samples of water from wells in Grant, Haskell, and Stevens Counties.

Iron(parts per million)

Number of samples

Grant County

Haskell County

Stevens County

Total

Less than 0.1

3

0

4

7

0.1-1.0

11

17

14

42

1.1-2.0

7

4

2

13

2.1-3.0

1

3

2

6

3.1-4.0

0

0

1

1

4.1-5.0

0

0

0

0

5.1-6.0

0

1

0

1

6.1-7.0

0

0

0

0

7.1-8.0

0

0

1

1

More than 8.0

3

1

2

6

Total

25

26

26

77

Fluoride--Although determinable quantities of fluoride are not as common as fairly large quantities of the other constituents of natural water, it is desirable to know the amount of fluoride in water that is likely to be used by children. Fluoride in drinking water has been shown to be associated with the dental defect known as mottled 'enamel, which may appear on the teeth of children during the period of formation of the permanent teeth. It has been stated that waters containing one part or more per million of fluoride are likely to produce mottled enamel on the teeth of children, although the effect of one part per million generally is not very serious (Dean, 1936). If the water contains as much as four parts per million of fluoride, 90 percent of the children drinking the water are likely to have mottled enamel, and 35 percent or more of the children will have moderately or badly mottled enamel.

Twenty-eight of the 77 samples collected in Grant, Haskell, and Stevens Counties contained one or more parts per million of fluoride (Table 17). Of these, 18 samples were from wells in Grant County, five were from Haskell County, and five were from Stevens County. The fluoride content of the water samples ranged from 0.2 to 3 parts per million.

Table 17--Fluoride content of samples of water from wells in Grant, Haskell, and Stevens Counties.

Fluoride(parts per million)

Number of samples

Grant County

Haskell County

Stevens County

Total

Less than 0.5

2

10

11

23

0.5-0.9

5

11

10

26

1.0-1.4

4

5

5

14

1.5-1.9

7

0

0

7

2.0-2.9

6

0

0

6

More than 2.9

1

0

0

1

Total

25

26

26

77

The fluoride content of water from wells in this area is illustrated in Figure 17. Most of the high-fluoride waters in southwestern Kansas are believed to be derived from the Dakota formation. High-fluoride waters in other formations generally seem to be the result of contamination by waters from the Dakota formation. In Stanton and Morton counties (Latta, 1941, and McLaughlin, 1942) high-fluoride waters from the Dakota formation move eastward into the Tertiary sediments, causing the waters in them to have a relatively high fluoride content. The Tertiary sediments in Grant, Haskell, Stanton, and parts of Morton and Stevens Counties overlie the Dakota formation; hence water in the Tertiary and overlying sediments probably is contaminated by high-fluoride waters from the underlying Dakota formation. The fluoride content of the ground water south of the Cimarron River in Morton and Stevens Counties is much lower than it is north of the river. This probably is caused by (1) the absence of the Dakota formation south of Cimarron River (except in northern Stevens County), (2) the slope of the water table in the vicinity of the Cimarron River, which prevents ground water moving from areas north and west of the river to areas south and east of the river (see explanation, page 62), and (3) the dilution of the ground water by the relatively rapid recharge of the ground-water reservoir in the dune-sand areas south of the river. In northern Stevens County, where the Tertiary and Quaternary sediments are underlain by the Dakota formation and where there is no dune sand to facilitate recharge, the fluoride content of ground water is higher than in any other part of the county (Fig. 17).

Figure 17--Map showing the fluoride content of water from wells in Grant, Haskell, and Stevens counties.

The fluoride content of water from wells in northeastern Grant County and the northeastern half of Haskell County is very low. This seems to have been caused by the movement of low-fluoride water into this area from the Finney sand plain where the recharge of the ground-water reservoir is so rapid that the ground water has a low-fluoride content even though the water-bearing material is underlain by the Dakota formation. (Compare the fluoride content of ground water as shown in Figure 17 with the direction of movement of ground water as shown on Plate 1.)

Water for irrigation--The suitability of water for irrigation is commonly believed to depend mainly on the quantity of soluble salts and on the ratio of the quantity of sodium to the quantity of sodium, calcium, and magnesium. The quantity of chloride may be large enough to affect the use of the water, and in some areas there may be other constituents, such as boron, in sufficient quantity to cause difficulty. In a discussion of the interpretation of analyses with reference to irrigation in southern California, Scofield (1933) states that if the concentration of dissolved salts is less than 700 parts per million there is not much probability of harmful effects in irrigation, but that if it exceeds 2,100 parts per million there is a strong probability of damage either to the crops, to the land, or to both. Water containing less than 50 percent sodium (the percentage being calculated as 100 times the ratio of the sodium to all the bases, in equivalents) is not likely to be injurious, but if it contains more than 60 percent sodium its use is inadvisable. Similarly, less than 142 parts per million of chloride is not objectionable, but more than 355 parts per million of chloride is undesirable. It is recognized that the harmfulness of irrigation water is so dependent on the types of land and crops, on the manner of use, and on the drainage that no definite limits can be adopted.

All but six of the samples of water collected in Grant, Haskell, and Stevens Counties were within the limits suggested by Scofield for waters safe for use in irrigation. Six of the water samples contained more than 700 parts per million of dissolved solids but none contained more than 2,100 parts of dissolved solids-the upper limit set by Scofield.

Sanitary Considerations

The analyses of water that are given in Table 11, Table 12, and Table 13 show only the amounts of dissolved mineral matter in the water and do not indicate the sanitary quality of the water. An abnormal amount of certain mineral matter, such as nitrate, however, may indicate pollution of the water.

Much of the population of Grant, Haskell, and Stevens Counties is dependent upon private water supplies from wells, and every precaution should be taken to protect these supplies from pollution. A well should not be constructed where there are possible sources of pollution, such as barnyards, privies, and cesspools, and every, well should be tightly sealed to a level somewhat below that of the water table. Dug wells are more likely to be contaminated from surface water than are drilled wells, chiefly because dug wells generally are not effectively cased or sealed at the surface. Drilled wells generally are well protected by the casing, although many are poorly sealed at the top.

Quality in Relation to Water-bearing Formations

The quality of water from the principal water-bearing formations in Grant, Haskell, and Stevens Counties is shown in Figure 18 and is discussed below.

Figure 18--Map showing the fluoride content of water from wells in Grant, Haskell, and Stevens counties.

Pliocene and Pleistocene deposits--The Pliocene deposits comprising the Laverne and Rexroad (?) formations and Pleistocene deposits comprising the Meade formation yield water to most of the wells in the Grant-Haskell-Stevens area, and many of the wells' obtain water from two or more of these formations. The ground, water in the sediments above the Dakota formation may be considered a single body of water because the water-bearing formations above the Dakota are lithologically similar and because there are no impermeable beds that separate entirely the water of one formation from that of another. For these reasons, the quality of water in all the Pliocene and Pleistocene formations will be discussed in one section. All but three wells listed in Table 11, Table 12, and Table 13 get water from the Rexroad (?), Meade, or Laverne formations; hence the discussion of quality of water in the preceding pages applies almost entirely to water from these formations.

The quality of water in the Pliocene and Pleistocene formations is not uniform throughout the area but has been modified in different areas by different conditions. As explained above, the fluoride content (Fig. 17) of water from these formations has been modified by recharge and by lateral movement of ground water. In general, the ground water in Haskell County is softer than that in Grant and Stevens Counties (Table 15), and the ground water in Grant County is of poorer quality than in the remainder of the area.

Alluvium--Samples of water were collected from three wells in the alluvium of the Cimarron River (wells 106, 119, and 253, Tables 11 and 13). The total dissolved solids in these waters ranged from 337 to 729 parts per million and the hardness ranged from 220 to 402 parts per million. The fluoride content of waters from these wells was relatively high (1.1, 1.6, and 1.8 parts per million).